Due to the wide band gap energy and high breakdown electric field of GaN, heterostructure transistors made from it are promising candidates for high power and high frequency applications. However, one issue that prevents the wide deployment of GaN HEMTs is their reliability. Research has been actively trying to improve the reliability of these devices. In spite of this, detailed understanding o...

Shot noise: Fluctuations of the current flowing through a device that result from the discreteness of the charge carrier. Shot noise provides information on the charge carriers and the transport mechanism in the device. The shot noise measurements in semiconductor heterostructure devices shed light on how the devices operate, beyond information provided by the electrical conductance. The shot n...

Recent progress in the field of Cu(In,Ga)Se2 (CIGS) thin film solar cell technology is briefly reviewed. New wide-bandgap Inx(OOH,S)y and ZnSx(OH)yOz buffers for CIGS solar cells have been developed. Advances have been made in the film deposition by the growth process optimization that allows the control of film properties at the microand nanolevels. To improve the CIGS cell junction characteri...

The use of templating method to synthesize the vanadyl 2,9,16,23-tetraphenoxy-29H,31H-phthalocyanine (VOPcPhO):[6,6]-phenyl C71 butyric acid methyl ester (PC71BM) composite nanotubes is presented here. VOPcPhO is a p-type material and PC71BM is an n-type material which acts as an electron donor and electron acceptor, respectively. Both materials have been studied due to their potential applicat...

Thermally annealed bilayer heterojunction was shown to be an alternative approach to form the bulk-heterojunction (BHJ) structure and yield superior device performance compared to blend-solution-processed BHJ organic photovoltaic (OPV) devices. The best poly(3-hexylthiophene) (P3HT)/[6,6]phenyl-C61-butyric acid methyl ester (PCBM) based bilayer structure OPV showed an external quantum efficienc...

MoS2, as a typical transition metal dichalcogenide, has attracted great interest because of its distinctive electronic, optical, and catalytic properties. However, its advantages of strong light absorption and fast intralayer mobility cannot be well developed in the usual reported monolayer/few-layer structures, which make the performances of MoS2-based devices undesirable. Here, large-area, hi...

A novel two-step solution approach is put forward to design a unique three dimensional (3D) porous ZnO-SnS p-n heterojunction under mild conditions. This special 3D structure is induced via flower-like ZnO in which SnS serves as an efficient photosensitizer to improve the light harvesting across the whole visible range. A profound investigation of the mechanism shows that this 3D porous ZnO-SnS...